[Stoves] Sawdust Gasification / retort

scda2 at t-online.de scda2 at t-online.de
Sat May 23 03:12:14 CDT 2015


Dear Tom,
when i fill the 2 oil drums mentioned in my post fom 20th "mobile adam-retort" with saw dust or wood chips (preferable) it might work.
its just a matter of time and waste fuel to burn  get the biomass carbonized.
With wood loaded  it takes about 3 hours to get the wood  to above 300°C
You want me to do it next week? We had a week of rain and cold (3°C) in Germany so it was no fun to work outside.
Best
Chris



-----Original-Nachricht-----
Betreff: [Stoves] Sawdust Gasification
Datum: Thu, 21 May 2015 20:12:54 +0200
Von: Tom Reed <tombreed2010 at gmail.com>
An: "stoves at lists.bioenergylists.org" <stoves at lists.bioenergylists.org>

Dear List

One of the benefits of the TLUD stove working on wood chips is that it produces 20% charcoal, which can be sequestered, removing 38 tons of CO2 from circulation for each           ton of wood gasified (20% due to formation of charcoal from the lignin and using the gas from the cellulose (renewable) in place of propane, natural gas of coal gas.  

If we could gasify sawdust, it would bring another, typically dry, source of fuel into the picture.  However, the particle size of sawdust does not permit TLUD operation.  Does anyone have a suggestion of how to gasify sawdust?

TOM REED 

Thomas B Reed 
280 Hardwick Rd
Barre, MA 01005
508 353 7841

> On May 20, 2015, at 2:13 PM, stoves-request at lists.bioenergylists.org wrote:
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> Today's Topics:
> 
>   1. Re: big TLUD (Energies Naturals C.B.)
>   2. Re: big TLUD (Crispin Pemberton-Pigott)
>   3. Giving up? ?mobile adam-retort? 4 photos (scda2 at t-online.de)
>   4. Re: big TLUD (Frank Shields)
>   5. Re: Giving up? ?mobile adam-retort? 4 photos (Frank Shields)
>   6. Re: big TLUD (Paul Anderson)
>   7. Giving up? ?mobile adam-retort? 3 additional drawings
>      (scda2 at t-online.de)
> 
> 
> ----------------------------------------------------------------------
> 
> Message: 1
> Date: Wed, 20 May 2015 20:57:04 +0200
> From: "Energies Naturals C.B." <energiesnaturals at gmx.de>
> To: Discussion of biomass cooking stoves
>    <stoves at lists.bioenergylists.org>
> Subject: Re: [Stoves] big TLUD
> Message-ID: <20150520205704.1291c4c6c4b03cf4fa290f12 at gmx.de>
> Content-Type: text/plain; charset=ISO-8859-1
> 
> Hallo "big TLUDers",
> 
> as I see from the various experiences and comments, the cross section of a big TLUD is to some extent limited.
> That means that in order to build a bigger unit, it has to grow by lenght, which in turn must enhance the resistance to the primary air flow. From Imberts we know that the relation between fuel size and hearth or throat is crucial.
> There must be enough space left between the particles to allow for a adequate air/gas flow.
> 
> My question: Does anyone have a clue on the matter of fuel size in TLUDs ?
> 
> Is it possible that larger diameters ask for larger chunks which in turn provide more space between them and ideally spread the upflowing air more uniformly?
> 
> Rolf
> 
> 
> 
> On Sat, 16 May 2015 22:40:14 -0500
> Paul Anderson <psanders at ilstu.edu> wrote:
> 
>> Char-makers,
>> 
>> This good discussion on the Stoves Listserv is being shared with the 
>> Biochar Listserv.   Let discussions proceed on each and both and see 
>> what happens.
>> 
>> It is great to see so much discussion.   And Bill's video of his 350 
>> gallon unit is very informative.   We await info and photos of the 500 
>> gallon unit he is making now.
>> 
>> Bill wrote:
>>> the larger the diameter of the TLUD, the greater the chance that the 
>>> pyrolysis front will not reach the hearth in all areas at the same 
>>> time.  If this happens you risk overheating tha hearth if you wait for 
>>> all the fuel to pyrolyse and burn some of the biochar. 
>> I completely agree.  And when we report on our actual experience, please 
>> specify the diameter (which is probably more important that the volume).
>> 
>> Diameters:
>> 1.   A 200 Liter (55 gal) drum or barrel is about 23 inches (58 cm) in 
>> diameter.   And that works rather well in the Jolly Roger Ovens (J-ROs) 
>> and similar units.
>> 
>> 2.   From Bill's video, his unit 350 gallon (over 1000 liter) unit is 
>> quite tall and has a diameter about the same as at 55 gal drum. It is 
>> good to see that it works well.
>> 
>> 3.  If I remember correctly, Alex's largest unit was 42 inch diameter 
>> (107 cm) and had problems with uneven descent of the Migratory Pyrolytic 
>> Front (MPF).   That matches well with Bill comment that is quoted above.
>> 
>> So, is Bill's 500 gal unit even taller but still "slender"?   And how 
>> well does it work?
>> 
>> An interesting question is about the possible favorable impact of having 
>> some of the following changes in the big TLUDs:
>> 
>> A.  Impact of a tapering the inside diameter in the lower section. But 
>> as I think more about that, I have my doubts if it will resolve the 
>> irregular MPF issue.
>> 
>> B.  impact of having sensors around the circumference of the TLUD at 
>> perhaps 1 meter vertical distances.   And if the temperature (indicating 
>> the MPF) is greater on one side too soon, EITHER
>> inject addition primary air via tuyers (nozzels) on the colder sides to 
>> hasten the MPF in those areas, OR
>> inject a bit of water into the area of the hot side to slow its movement 
>> a bit.
>> 
>> With serious char-making devices such as what Bill has, a relatively 
>> small cost would be the welding of some pipe nipples (each with a screw 
>> on cap) at the appropriate places for the air or water entries (B above) 
>> and where thermocouples could be inserted to check temperatures 
>> including in the center of the cylindrical column of fuel.
>> 
>> If anyone tries these ideas, please let us all know you progress and 
>> results.
>> 
>> Paul
>> 
>> Doc  /  Dr TLUD  /  Prof. Paul S. Anderson, PhD
>> Email:  psanders at ilstu.edu
>> Skype: paultlud      Phone: +1-309-452-7072
>> Website:  www.drtlud.com
>> 
>>> On 5/14/2015 8:20 PM, biocharFIRST . wrote:
>>> I don't know how big you can build a TLUD. However about three years 
>>> ago I built a 350 gallon TLUD that is working out very well, except 
>>> for the fact that we do not have a use for the sen gas where the TLUD 
>>> is now located at my home.  You can see a video at, 
>>> vhttps://www.youtube.com/watch?v=5Kfr4NRhJ0s.
>>> 
>>> Currently we have almost completed a 500 gallon TLUD that is designed 
>>> to exhaust  all of the sen gas down a tube in the center of the tank 
>>> so the heat from the gas can easily be captured for various uses.
>>> r be uniformly dry, and the larger the diameter of the TLUD, the 
>>> greater the chance that the pyrolysis front will not reach the hearth 
>>> in all areas at the same time.  If this happens you risk overheating 
>>> tha hearth if you wait for all the fuel to pyrolyse and burn some of 
>>> the biochar.  If you shut off the primary before pyrolysis is complete 
>>> you will get some smoke and some biomass that is not completely 
>>> pyrolysed.
>>> 
>>> On Thu, May 14, 2015 at 4:46 PM, Crispin Pemberton-Pigott 
>>> <crispinpigott at outlook.com <mailto:crispinpigott at outlook.com>> wrote:
>>> 
>>>    AJH >Yes and/or premixing but why does burning rice hulls tend
>>>    more to the
>>>    blue flame?
>>> 
>>>    Lower volatiles? The carbon/hydrogen ratio is not the same as
>>>    wood. Maybe
>>>    that helps.
>>> 
>>>    Apparently the reactions can be shifted from CO to H2 by using
>>>    different
>>>    catalysts:
>>>    Crispin
>>> 
>>>    From http://www.sciencedirect.com/science/article/pii/0141460786900727
>>> 
>>>    Catalytic gasification of rice hull and other biomass. The general
>>>    effect of
>>>    catalyst.
>>> 
>>>    Abstract:
>>>    Thermochemical decomposition and catalytic conversion of rice hull
>>>    and some
>>>    other cellulosic materials in a fluidized bed reactor containing
>>>    different
>>>    catalysts as the bed material were studied. The use of catalyst
>>>    invariably
>>>    gave gas yields above that of the non-catalyzed gasification
>>>    process and
>>>    also changed the product distribution according to the nature of the
>>>    catalyst. Generally, an acidic catalyst favored the formation of
>>>    carbon
>>>    monoxide and olefins while a supported-metal catalyst increased
>>>    the amounts
>>>    of hydrogen and carbon dioxide. Nickel catalyst yielded as much as 60%
>>>    hydrogen at a reaction temperature of 650?C. The gas yield and product
>>>    distribution are mainly decided by the properties of the catalyst
>>>    and less
>>>    by the properties of the biomass.
>>> 
>>>    _______________________________________________
>>>    Stoves mailing list
>>> 
>>>    to Send a Message to the list, use the email address
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>>>    site:
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>>> 
>>> 
>>> 
>>> -- 
>>> http://www.ithakajournal.com
>>> 
>>> 
>>> _______________________________________________
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>>> 
>> 
> 
> 
> -- 
> Energies Naturals C.B. <energiesnaturals at gmx.de>
> 
> 
> 
> ------------------------------
> 
> Message: 2
> Date: Wed, 20 May 2015 15:30:37 -0400
> From: Crispin Pemberton-Pigott <crispinpigott at outlook.com>
> To: "'Discussion of biomass cooking stoves'"
>    <stoves at lists.bioenergylists.org>
> Subject: Re: [Stoves] big TLUD
> Message-ID: <COL401-EAS266FA6659A75E99A55105E3B1C20 at phx.gbl>
> Content-Type: text/plain; charset="us-ascii"
> 
> Dear Rolf
> 
> I have a general rule (which results from empirical testing) which is that
> the fuel particle has to be smaller than 1/6th of the diameter of the
> chamber. At 6 it is iffy - problems abound with the fire going out and
> difficulty igniting, high excess air, poor potential for secondary air
> management etc.
> 
> There is an upper limit too but I am not sure where it is. It is less than
> 25 and I suspect above 20 is a cause for concern. 
> 
> Packing density is an issue but it is an indicator, but 'the issue'.  "The
> issue" is the superficial and actual velocity of air moving through the
> system.
> 
> The numbers are influenced by the temperature of the surrounds so it is not
> as simple as saying 'here are the hard numbers'.  When you get to mixing
> different sizes together you will have to work with the actual air flow
> rate.
> 
> Regards
> Crispin
> .
> 
> Hallo "big TLUDers",
> 
> as I see from the various experiences and comments, the cross section of a
> big TLUD is to some extent limited.
> That means that in order to build a bigger unit, it has to grow by lenght,
> which in turn must enhance the resistance to the primary air flow. From
> Imberts we know that the relation between fuel size and hearth or throat is
> crucial.
> There must be enough space left between the particles to allow for a
> adequate air/gas flow.
> 
> My question: Does anyone have a clue on the matter of fuel size in TLUDs ?
> 
> Is it possible that larger diameters ask for larger chunks which in turn
> provide more space between them and ideally spread the upflowing air more
> uniformly?
> 
> Rolf
> 
> 
> 
> ------------------------------
> 
> Message: 3
> Date: Wed, 20 May 2015 22:35:24 +0200
> From: "scda2 at t-online.de" <scda2 at t-online.de>
> To: stoves at lists.bioenergylists.org
> Subject: [Stoves] Giving up? ?mobile adam-retort? 4 photos
> Message-ID: <570151302555cf00cccae11.53491204 at email.t-online.de>
> Content-Type: text/plain; charset="utf-8"
> 
> Giving up? ?mobile adam-retort?
> 
> Dear All, 
> just sharing a few experience with my ?mobile adam-retort?
> I did test run#5 and I might give up, as it?s too difficult to operate the retort in a smokeless way (burning smoke). And without reduced smoke there is little sense to operate such a unit near saw mills, carpenter shops in suburbs, etc.
> What?s stunning me:  during syngas operation if volatiles are passing through the unit, heavy volatiles are leaving chimney. Once I close chimney, syngas is overflowing from fire box, and burned syn gas escapes into air in kind clear volatiles. OK, you will say: larger ducts, larger diameters of channels?
> But how to get this done with a ?light weight ? unit (~130kg).
> 
> Photos 1: Overflowing of syn gas from fire box when chimney (~500?C) closed. 4th hr of operation.
> 
> Another phenomena, volatiles are leaving chimney kind of clear volatiles, once they get in contact with ambient air- heavy smoke develops.
> 
> Photo2 : 3rd hour of operation. Shortly before large syn gas production starts (chimney ~300?C), fire wood was removed shortly after. AGiP drums just serves as a table to hold thermometer. .
> 
> Photo3: big stress on materials (!), of retort is left open until gasification dies, chimney temp rises to ~650?C, Temperature in oil drums with wood comes to 600?C also. ( = high quality , high temperature charcoal). 
> 
> Efficiency about 30% (dry weight) or ~25% of waste wood in fire box counted. Operation about 5 hours (3hrs drying + 2hrs syn gas). ~110kg of wood dry weight loaded into 2 oil drums, ~35kg of charcoal received. ~15kg of waste wood (dry weight) burnt. Cost of retort ~500US$ (?) mass production.
> 
> Fig. 1 Drawing to explain function. (Unit Is tilted 90? for loading/unloading).
> 22 (chimney), 23 (opening) not needed
> Fire under 1st oil drum (filled with wood) is producing syngas which is burned and is heating 2nd oil drum in caskade effect...
> 
> Cheers Chris ADAM
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> 
> ------------------------------
> 
> Message: 4
> Date: Wed, 20 May 2015 13:35:37 -0700
> From: Frank Shields <franke at cruzio.com>
> To: Discussion of biomass cooking stoves
>    <stoves at lists.bioenergylists.org>
> Subject: Re: [Stoves] big TLUD
> Message-ID: <EE6C234A-607E-4C77-BEE8-2119737A8D53 at cruzio.com>
> Content-Type: text/plain; charset=utf-8
> 
> Dear Crispin, and Stovers,
> 
> Interesting topic. And there must be an optimum and way to measure and determine what this is.
> 
> I?m thinking its air channeling (sections of high air movement) that gives the problem resulting in un-even air front. 
> 
> In addition to size of particles.  Particles must be of a size able to ignite from radiant heat from neighboring particles. At stove camp they stated a value - something like no more than three times the size of the match(?). And that should apply here I would think. We can start with small particles on top to light and gradually go to larger particles as the flame front moves down? OR does that mean larger particles can be no more than three times the smaller particles so all neighbor particles will light. A test of particle distribution and uniformity coefficient might be a good test. 
> 
> How can we test for channeling? 
> Perhaps: Have air flowing through the system then add pure CO2 and measure the CO2 increase at the other end. With even flow there should be a sharp increase but with channeling it would be a gradual increase?
> 
> Regards
> 
> 
> Frank
> 
> 
> 
> Frank Shields
> franke at cruzio.com
> 
> 
>> On May 20, 2015, at 12:30 PM, Crispin Pemberton-Pigott <crispinpigott at outlook.com> wrote:
>> 
>> Dear Rolf
>> 
>> I have a general rule (which results from empirical testing) which is that
>> the fuel particle has to be smaller than 1/6th of the diameter of the
>> chamber. At 6 it is iffy - problems abound with the fire going out and
>> difficulty igniting, high excess air, poor potential for secondary air
>> management etc.
>> 
>> There is an upper limit too but I am not sure where it is. It is less than
>> 25 and I suspect above 20 is a cause for concern. 
>> 
>> Packing density is an issue but it is an indicator, but 'the issue'.  "The
>> issue" is the superficial and actual velocity of air moving through the
>> system.
>> 
>> The numbers are influenced by the temperature of the surrounds so it is not
>> as simple as saying 'here are the hard numbers'.  When you get to mixing
>> different sizes together you will have to work with the actual air flow
>> rate.
>> 
>> Regards
>> Crispin
>> .
>> 
>> Hallo "big TLUDers",
>> 
>> as I see from the various experiences and comments, the cross section of a
>> big TLUD is to some extent limited.
>> That means that in order to build a bigger unit, it has to grow by lenght,
>> which in turn must enhance the resistance to the primary air flow. From
>> Imberts we know that the relation between fuel size and hearth or throat is
>> crucial.
>> There must be enough space left between the particles to allow for a
>> adequate air/gas flow.
>> 
>> My question: Does anyone have a clue on the matter of fuel size in TLUDs ?
>> 
>> Is it possible that larger diameters ask for larger chunks which in turn
>> provide more space between them and ideally spread the upflowing air more
>> uniformly?
>> 
>> Rolf
>> 
>> _______________________________________________
>> Stoves mailing list
>> 
>> to Send a Message to the list, use the email address
>> stoves at lists.bioenergylists.org
>> 
>> to UNSUBSCRIBE or Change your List Settings use the web page
>> http://lists.bioenergylists.org/mailman/listinfo/stoves_lists.bioenergylists.org
>> 
>> for more Biomass Cooking Stoves,  News and Information see our web site:
>> http://stoves.bioenergylists.org/
>> 
> 
> 
> 
> 
> ------------------------------
> 
> Message: 5
> Date: Wed, 20 May 2015 13:43:05 -0700
> From: Frank Shields <franke at cruzio.com>
> To: "scda2 at t-online.de" <scda2 at t-online.de>,    Discussion of biomass
>    cooking stoves <stoves at lists.bioenergylists.org>
> Subject: Re: [Stoves] Giving up? ?mobile adam-retort? 4 photos
> Message-ID: <156C8F05-1CBC-4F8A-8DA0-BCD36F89478D at cruzio.com>
> Content-Type: text/plain; charset=utf-8
> 
> I?m wondering if picture #2 is more water vapor than smoke?  An in lab experiment i did produced the same looking ?smoke? and clouded the room but I later thought it water vapor. 
> 
> Frank
> 
> 
> 
> Frank Shields
> franke at cruzio.com
> 
> 
>> On May 20, 2015, at 1:35 PM, scda2 at t-online.de wrote:
>> 
>> Giving up? ?mobile adam-retort?
>> 
>> Dear All, 
>> just sharing a few experience with my ?mobile adam-retort?
>> I did test run#5 and I might give up, as it?s too difficult to operate the retort in a smokeless way (burning smoke). And without reduced smoke there is little sense to operate such a unit near saw mills, carpenter shops in suburbs, etc.
>> What?s stunning me:  during syngas operation if volatiles are passing through the unit, heavy volatiles are leaving chimney. Once I close chimney, syngas is overflowing from fire box, and burned syn gas escapes into air in kind clear volatiles. OK, you will say: larger ducts, larger diameters of channels?
>> But how to get this done with a ?light weight ? unit (~130kg).
>> 
>> Photos 1: Overflowing of syn gas from fire box when chimney (~500?C) closed. 4th hr of operation.
>> 
>> Another phenomena, volatiles are leaving chimney kind of clear volatiles, once they get in contact with ambient air- heavy smoke develops.
>> 
>> Photo2 : 3rd hour of operation. Shortly before large syn gas production starts (chimney ~300?C), fire wood was removed shortly after. AGiP drums just serves as a table to hold thermometer. .
>> 
>> Photo3: big stress on materials (!), of retort is left open until gasification dies, chimney temp rises to ~650?C, Temperature in oil drums with wood comes to 600?C also. ( = high quality , high temperature charcoal). 
>> 
>> Efficiency about 30% (dry weight) or ~25% of waste wood in fire box counted. Operation about 5 hours (3hrs drying + 2hrs syn gas). ~110kg of wood dry weight loaded into 2 oil drums, ~35kg of charcoal received. ~15kg of waste wood (dry weight) burnt. Cost of retort ~500US$ (?) mass production.
>> 
>> Fig. 1 Drawing to explain function. (Unit Is tilted 90? for loading/unloading).
>> 22 (chimney), 23 (opening) not needed
>> Fire under 1st oil drum (filled with wood) is producing syngas which is burned and is heating 2nd oil drum in caskade effect...
>> 
>> Cheers Chris ADAM<IMG_5050 overflow.JPG><IMG_5023 smoke1.JPG><IMG_5039 glow.JPG><detail drawing1 mobile.JPG>_______________________________________________
>> Stoves mailing list
>> 
>> to Send a Message to the list, use the email address
>> stoves at lists.bioenergylists.org
>> 
>> to UNSUBSCRIBE or Change your List Settings use the web page
>> http://lists.bioenergylists.org/mailman/listinfo/stoves_lists.bioenergylists.org
>> 
>> for more Biomass Cooking Stoves,  News and Information see our web site:
>> http://stoves.bioenergylists.org/
>> 
> 
> 
> 
> 
> ------------------------------
> 
> Message: 6
> Date: Wed, 20 May 2015 16:03:41 -0500
> From: Paul Anderson <psanders at ilstu.edu>
> To: Discussion of biomass cooking stoves
>    <stoves at lists.bioenergylists.org>
> Subject: Re: [Stoves] big TLUD
> Message-ID: <555CF6AD.5070501 at ilstu.edu>
> Content-Type: text/plain; charset=windows-1252; format=flowed
> 
> Rolf,
> 
> Fuel size is related to the dwell-time (time the fuel is exposed to the 
> heat).   Tom Reed says it takes about one hour of exposure to pyrolyze 
> through about one inch (2.5 cm) of wood FROM ONE SIDE.   So think of 
> radius of the fuel or its smallest dimension.
> 
> And the TLUD height (which relates to the duration of the operation) 
> will give some indication of the available time.
> 
> 1.  So, you could have a 2 inch smallest-dimension piece of fuel near 
> the top of the fuel pile in a one hour of operation TLUD.   But the same 
> piece of wood if inserted vertically would have an hour of heat at the 
> top but less than 30 minutes or even only 15 minutes for the end that is 
> near the bottom.   The bottom part will be off-gasing (giving smoke) if 
> it is removed when the majority of the pyrolysis has completed.   
> Waiting for that piece to pyrolyze in a functioning unit will result in 
> the loss of char that is burning to give the heat for pyrolysis.
> 
> Vertical pieces of wood work very well, but it is good to have a bottom 
> layer of smaller pieces.
> 
> 2.  The other big variable is the control of the two air supplies. The 
> ability to SHUT DOWN the primary air is extremely important, and widely 
> overlooked.   Ideally, the MPF (Migratory Pyrolytic Front) will descend 
> rather uniformly.   But if it does not (and this problem increases in 
> likelihood in larger TLUDs), pyrolysis and char making can be kept 
> somewhat under control if the primary air is severely restricted.  Keep 
> the HEAT (not the fire itself) inside the fuel chamber and the off-gases 
> will be created, the fire at the top (burning the gases) can be 
> sustained and also controlled for minimal smoke even though the fire 
> inside the TLUD has dropped to the bottom of the fuel chamber.   Not a 
> perfect run cycle, but probably some reasonable char production 
> (compared with letting the fire race away inside the fuel chamber).
> 
> 3.  The ability to supplement (increase) the air flows (both of them, 
> but separately) is a major factor for control and for reducing the 
> dependence on uniformity of fuel sizes.   Yesterday, in a TLUD of two 
> small barrels, the final stages of a 45 minute operation had too much 
> pyrolysis occurring, giving lots of flames (shooting 4 inches above the 
> 3 foot chimney) and some visible black smoke. Instead of cutting back 
> the primary air, I used a portable blower (with a 12 V DC motorcycle 
> battery) to increase only the secondary air, and the smokiness 
> disappeared and the flames were only half way up the chimney.
> 
> NOTE:  This gave great heat supply, but for a shorter time period than 
> if I had cut back on the primary air (giving more time for pyrolysis).
> 
> Paul
> 
> Doc  /  Dr TLUD  /  Prof. Paul S. Anderson, PhD
> Email:  psanders at ilstu.edu
> Skype: paultlud      Phone: +1-309-452-7072
> Website:  www.drtlud.com
> 
>> On 5/20/2015 2:30 PM, Crispin Pemberton-Pigott wrote:
>> Dear Rolf
>> 
>> I have a general rule (which results from empirical testing) which is that
>> the fuel particle has to be smaller than 1/6th of the diameter of the
>> chamber. At 6 it is iffy - problems abound with the fire going out and
>> difficulty igniting, high excess air, poor potential for secondary air
>> management etc.
>> 
>> There is an upper limit too but I am not sure where it is. It is less than
>> 25 and I suspect above 20 is a cause for concern.
>> 
>> Packing density is an issue but it is an indicator, but 'the issue'.  "The
>> issue" is the superficial and actual velocity of air moving through the
>> system.
>> 
>> The numbers are influenced by the temperature of the surrounds so it is not
>> as simple as saying 'here are the hard numbers'.  When you get to mixing
>> different sizes together you will have to work with the actual air flow
>> rate.
>> 
>> Regards
>> Crispin
>> .
>> 
>> Hallo "big TLUDers",
>> 
>> as I see from the various experiences and comments, the cross section of a
>> big TLUD is to some extent limited.
>> That means that in order to build a bigger unit, it has to grow by lenght,
>> which in turn must enhance the resistance to the primary air flow. From
>> Imberts we know that the relation between fuel size and hearth or throat is
>> crucial.
>> There must be enough space left between the particles to allow for a
>> adequate air/gas flow.
>> 
>> My question: Does anyone have a clue on the matter of fuel size in TLUDs ?
>> 
>> Is it possible that larger diameters ask for larger chunks which in turn
>> provide more space between them and ideally spread the upflowing air more
>> uniformly?
>> 
>> Rolf
>> 
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>> 
> 
> 
> 
> 
> ------------------------------
> 
> Message: 7
> Date: Wed, 20 May 2015 23:13:07 +0200
> From: "scda2 at t-online.de" <scda2 at t-online.de>
> To: stoves at lists.bioenergylists.org
> Subject: [Stoves] Giving up? ?mobile adam-retort? 3 additional
>    drawings
> Message-ID: <491227133555cf8e32dbc15.21279557 at email.t-online.de>
> Content-Type: text/plain; charset="utf-8"
> 
> 
> If someone wants to go into it (additional drawings)
> 
> Fig.2 front view
> Fig.3 side view
> Fig.4 top view
> 
> Part list:
> 
> List of Reference:
> 
> 1, 2,    one, two or more containers 
> 3,    base plate 
> 4,    closure 
> 5,    Low chamber-frame 
> 6,    fireplace 
> 7,    passage opening 
> 8    sheet metal strip 
> 9,    channel 
> 10,    chimney pipe 
> 11,    upper Case 
> 12,    frame for unrolling 
> 13,    quarter-circular rounding 
> 14,    pivot point 
> 15,    tilt direction 
> 16,    opening underside container 
> 17,    smoke-burning zone by secondary air 
> 18,    pipe to connect the flue gases between modules  SKiP
> 19,    passage to connect the secondary air between modules  SKiP
> 20,    passage to connect the chimney gases in the upper case between modules  SKiP
> 21, passage opening for modular design   SKiP
> 22, chimney pipe with Bye-pass function and closing     SKiP
> 23,    passage opening with bye-pass function and closure    SKiP
> 
> 
> 
> 
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> 
> ------------------------------
> 
> Subject: Digest Footer
> 
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> 
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> 
> ------------------------------
> 
> End of Stoves Digest, Vol 57, Issue 19
> **************************************

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